Ring hole planning for external fixation frames

Abstract

An external fixation system includes first and second fixation members having first and second pluralities of mounting holes, respectively. The first and second plurality of holes are configured to receive first and second ends of a plurality of struts, each strut having a default or initial mounting position. A simulation of the correction may be performed with the struts in the default positions, but it may be determined that the correction is not achievable. Additional simulations of the correction may be performed with the ends of the struts in different mounting positions to determine if other mounting positions of the struts allow the correction to be completed. During the correction, if one of the struts reaches a maximum length, it may be disconnected and reconnected to a different mounting hole so that, after being reconnected, the strut may be further increased in length to continue the correction.

The invention claimed is: 
     
       1. A method of editing a default strut mounting point, the method comprising:
 displaying on a display device a virtual proximal fixation ring including a plurality of virtual proximal apertures extending through the virtual proximal fixation ring from a top surface to a bottom surface of the virtual proximal fixation ring; 
 displaying on the display device a virtual distal fixation ring including a plurality of virtual distal apertures extending through the virtual distal fixation ring from a top surface to a bottom surface of the virtual distal fixation ring; 
 displaying on the display device a virtual representation of a proximal portion of a strut positioned within a first one of the virtual proximal apertures in a first default proximal mounting position; 
 while the virtual representation of the proximal portion of the strut is positioned in the first default proximal mounting position, manually selecting the first default proximal mounting position via a user input device; 
 highlighting on the display device a second one of the virtual proximal apertures corresponding to a first non-default proximal mounting position while the first default proximal mounting position is selected; and 
 manually selecting the highlighted second one of the virtual proximal apertures with the user input device to edit the first default proximal mounting position to a first revised proximal mounting position, 
 wherein in the first revised proximal mounting position, the virtual representation of the proximal portion of the strut is positioned within the second one of the virtual proximal apertures. 
 
     
     
       2. The method of  claim 1 , further comprising displaying on the display device a virtual representation of a distal portion of the strut positioned within a first one of the virtual distal apertures in a first default distal mounting position. 
     
     
       3. The method of  claim 2 , further comprising selecting the virtual representation of the distal portion of the strut on the display device via the user input device. 
     
     
       4. The method of  claim 3 , further comprising highlighting on the display device a second one of the virtual distal apertures corresponding to a first non-default distal mounting position while the virtual representation of the distal portion of the strut is selected. 
     
     
       5. The method of  claim 4 , further comprising selecting the highlighted second one of the virtual distal apertures to edit the first default distal mounting position to a first revised distal mounting position. 
     
     
       6. The method of  claim 5 , wherein in the first revised distal mounting position, the virtual representation of the distal portion of the strut is positioned within the second one of the virtual distal apertures. 
     
     
       7. The method of  claim 1 , further comprising coupling a physical proximal fixation ring and a physical distal fixation ring to a patient, the physical proximal and distal fixation rings corresponding to the virtual proximal and distal fixation rings, respectively. 
     
     
       8. The method of  claim 7 , further comprising coupling a physical strut to the physical proximal fixation ring and to the physical distal fixation ring. 
     
     
       9. The method of  claim 8 , wherein the step of coupling the physical strut to the physical proximal fixation ring includes coupling a proximal portion of the physical strut to a first non-default physical proximal aperture in the physical proximal fixation ring corresponding to the first non-default proximal mounting position. 
     
     
       10. The method of  claim 7 , wherein the physical proximal fixation ring includes an indicator of a first default physical proximal aperture position corresponding to the first default proximal mounting position. 
     
     
       11. The method of  claim 7 , wherein the physical proximal fixation ring includes a first group of physical proximal apertures that are aligned in a first circumferential row. 
     
     
       12. The method of  claim 11 , wherein the physical proximal fixation ring includes a plurality of tabs extending radially outward of the first circumferential row. 
     
     
       13. The method of  claim 12 , wherein the physical proximal fixation ring includes a second group of physical proximal apertures that are aligned in a second circumferential row positioned within the plurality of tabs. 
     
     
       14. The method of  claim 13 , wherein the physical strut is one of a total of six physical struts that couple the physical proximal fixation ring to the physical distal fixation ring. 
     
     
       15. The method of  claim 14 , wherein each of the six physical struts is coupled to a physical proximal aperture in the second group.